106 ideas
2546 | Philosophy is a magnificent failure in its attempt to overstep the limits of our knowledge [McGinn] |
6052 | Definitions identify two concepts, so they presuppose identity [McGinn] |
6064 | Regresses are only vicious in the context of an explanation [McGinn] |
13252 | Some truths have true negations [Beall/Restall] |
6088 | Truth is a method of deducing facts from propositions [McGinn] |
13247 | A truthmaker is an object which entails a sentence [Beall/Restall] |
6084 | 'Snow does not fall' corresponds to snow does fall [McGinn] |
6085 | The idea of truth is built into the idea of correspondence [McGinn] |
6083 | The coherence theory of truth implies idealism, because facts are just coherent beliefs [McGinn] |
6086 | Truth is the property of propositions that makes it possible to deduce facts [McGinn] |
6087 | Without the disquotation device for truth, you could never form beliefs from others' testimony [McGinn] |
10688 | 'Equivocation' is when terms do not mean the same thing in premises and conclusion [Beall/Restall] |
13249 | (∀x)(A v B) |- (∀x)A v (∃x)B) is valid in classical logic but invalid intuitionistically [Beall/Restall] |
13243 | Excluded middle must be true for some situation, not for all situations [Beall/Restall] |
13242 | It's 'relevantly' valid if all those situations make it true [Beall/Restall] |
13246 | Relevant logic does not abandon classical logic [Beall/Restall] |
13245 | Relevant consequence says invalidity is the conclusion not being 'in' the premises [Beall/Restall] |
13254 | A doesn't imply A - that would be circular [Beall/Restall] |
13255 | Relevant logic may reject transitivity [Beall/Restall] |
13250 | Free logic terms aren't existential; classical is non-empty, with referring names [Beall/Restall] |
13235 | Logic studies consequence; logical truths are consequences of everything, or nothing [Beall/Restall] |
13238 | Syllogisms are only logic when they use variables, and not concrete terms [Beall/Restall] |
13234 | The view of logic as knowing a body of truths looks out-of-date [Beall/Restall] |
10690 | Formal logic is invariant under permutations, or devoid of content, or gives the norms for thought [Beall/Restall] |
13232 | Logic studies arguments, not formal languages; this involves interpretations [Beall/Restall] |
13241 | The model theory of classical predicate logic is mathematics [Beall/Restall] |
10691 | Logical consequence needs either proofs, or absence of counterexamples [Beall/Restall] |
13253 | There are several different consequence relations [Beall/Restall] |
13240 | A sentence follows from others if they always model it [Beall/Restall] |
10695 | Logical consequence is either necessary truth preservation, or preservation based on interpretation [Beall/Restall] |
10689 | A step is a 'material consequence' if we need contents as well as form [Beall/Restall] |
6051 | In 'x is F and x is G' we must assume the identity of x in the two statements [McGinn] |
6055 | Both non-contradiction and excluded middle need identity in their formulation [McGinn] |
6059 | Identity is unitary, indefinable, fundamental and a genuine relation [McGinn] |
2544 | Thoughts have a dual aspect: as they seem to introspection, and their underlying logical reality [McGinn] |
6042 | The quantifier is overrated as an analytical tool [McGinn] |
6067 | Existential quantifiers just express the quantity of things, leaving existence to the predicate 'exists' [McGinn] |
6069 | 'Partial quantifier' would be a better name than 'existential quantifier', as no existence would be implied [McGinn] |
6068 | We need an Intentional Quantifier ("some of the things we talk about.."), so existence goes into the proposition [McGinn] |
10696 | A 'logical truth' (or 'tautology', or 'theorem') follows from empty premises [Beall/Restall] |
13236 | Logical truth is much more important if mathematics rests on it, as logicism claims [Beall/Restall] |
10693 | Models are mathematical structures which interpret the non-logical primitives [Beall/Restall] |
13237 | Preface Paradox affirms and denies the conjunction of propositions in the book [Beall/Restall] |
10692 | Hilbert proofs have simple rules and complex axioms, and natural deduction is the opposite [Beall/Restall] |
6070 | Existence is a primary quality, non-existence a secondary quality [McGinn] |
6062 | Existence can't be analysed as instantiating a property, as instantiation requires existence [McGinn] |
6065 | We can't analyse the sentence 'something exists' in terms of instantiated properties [McGinn] |
22427 | To explain object qualities, primary qualities must be more than mere sources of experience [McGinn] |
6082 | If causal power is the test for reality, that will exclude necessities and possibilities [McGinn] |
6075 | Facts are object-plus-extension, or property-plus-set-of-properties, or object-plus-property [McGinn] |
18892 | Suppose a world where I'm from different gametes; add my gametes; which one is more me? [McGinn] |
12019 | McGinn falsely claims necessity of origin is a special case of the necessity of identity [Forbes,G on McGinn] |
6058 | Identity propositions are not always tautological, and have a key epistemic role [McGinn] |
6053 | Identity is as basic as any concept could ever be [McGinn] |
6043 | Type-identity is close similarity in qualities [McGinn] |
6044 | Qualitative identity is really numerical identity of properties [McGinn] |
6046 | Qualitative identity can be analysed into numerical identity of the type involved [McGinn] |
6045 | It is best to drop types of identity, and speak of 'identity' or 'resemblance' [McGinn] |
6066 | Existence is a property of all objects, but less universal than self-identity, which covers even conceivable objects [McGinn] |
6054 | Sherlock Holmes does not exist, but he is self-identical [McGinn] |
6047 | All identity is necessary, though identity statements can be contingently true [McGinn] |
6049 | Leibniz's Law says 'x = y iff for all P, Px iff Py' [McGinn] |
6048 | Leibniz's Law is so fundamental that it almost defines the concept of identity [McGinn] |
6050 | Leibniz's Law presupposes the notion of property identity [McGinn] |
13244 | Relevant necessity is always true for some situation (not all situations) [Beall/Restall] |
6080 | Modality is not objects or properties, but the type of binding of objects to properties [McGinn] |
6079 | If 'possible' is explained as quantification across worlds, there must be possible worlds [McGinn] |
6171 | Beliefs are states of the head that explain behaviour, and also items with referential truth-conditions [McGinn] |
22413 | Being red simply consists in looking red [McGinn] |
22415 | Relativity means differing secondary perceptions are not real disagreements [McGinn] |
22416 | Phenomenalism is correct for secondary qualities, so scepticism is there impossible [McGinn] |
22422 | Maybe all possible sense experience must involve both secondary and primary qualities [McGinn] |
22428 | You understood being red if you know the experience involved; not so with thngs being square [McGinn] |
22414 | You don't need to know how a square thing looks or feels to understand squareness [McGinn] |
22423 | Touch doesn't provide direct experience of primary qualities, because touch feels temperature [McGinn] |
22426 | We can perceive objectively, because primary qualities are not mind-created [McGinn] |
22412 | Lockean secondary qualities (unlike primaries) produce particular sensory experiences [McGinn] |
22421 | Could there be a mind which lacked secondary quality perception? [McGinn] |
22424 | Secondary qualities contain information; their variety would be superfluous otherwise [McGinn] |
22425 | The utility theory says secondary qualities give information useful to human beings [McGinn] |
7629 | We see objects 'directly' by representing them [McGinn] |
6081 | Necessity and possibility are big threats to the empiricist view of knowledge [McGinn] |
6071 | Scepticism about reality is possible because existence isn't part of appearances [McGinn] |
20653 | Six reduction levels: groups, lives, cells, molecules, atoms, particles [Putnam/Oppenheim, by Watson] |
4691 | If all mental life were conscious, we would be unable to see things, or to process speech [McGinn] |
2539 | Mental modules for language, social, action, theory, space, emotion [McGinn] |
2545 | Free will is mental causation in action [McGinn] |
2543 | Brains aren't made of anything special, suggesting panpsychism [McGinn] |
7388 | McGinn invites surrender, by saying it is hopeless trying to imagine conscious machines [Dennett on McGinn] |
2540 | Examining mind sees no brain; examining brain sees no mind [McGinn] |
3185 | Multiple realisability rules out hidden essences and experts as the source of water- and gold-concepts [McGinn] |
13239 | Judgement is always predicating a property of a subject [Beall/Restall] |
22420 | The indexical perspective is subjective, incorrigible and constant [McGinn] |
18410 | Indexical thought is in relation to my self-consciousness [McGinn] |
22417 | Indexicals do not figure in theories of physics, because they are not explanatory causes [McGinn] |
18402 | Indexical concepts are indispensable, as we need them for the power to act [McGinn] |
4690 | If meaning is speaker's intentions, it can be reduced to propositional attitudes, and philosophy of mind [McGinn] |
6077 | Semantics should not be based on set-membership, but on instantiation of properties in objects [McGinn] |
2547 | There is information if there are symbols which refer, and which can combine into a truth or falsehood [McGinn] |
6074 | Clearly predicates have extensions (applicable objects), but are the extensions part of their meaning? [McGinn] |
13248 | We can rest truth-conditions on situations, rather than on possible worlds [Beall/Restall] |
22418 | I can know indexical truths a priori, unlike their non-indexical paraphrases [McGinn] |
13233 | Propositions commit to content, and not to any way of spelling it out [Beall/Restall] |
2542 | Causation in the material world is energy-transfer, of motion, electricity or gravity [McGinn] |
6072 | If Satan is the most imperfect conceivable being, he must have non-existence [McGinn] |
6073 | I think the fault of the Ontological Argument is taking the original idea to be well-defined [McGinn] |